| 1. |
- Sorensen, S. L., et al.
(författare)
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Femtosecond pump-probe photoelectron spectroscopy of predissociative Rydberg states in acetylene
- 2000
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Ingår i: Journal of Chemical Physics. - : AIP Publishing. - 0021-9606 .- 1089-7690. ; 112:18, s. 8038-8042
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Tidskriftsartikel (refereegranskat)abstract
- We employ a pump-probe approach to molecular photoionization to study fast dissociation of Rydberg states in acetylene. By using time-resolved photoelectron spectroscopy to study the electronic state of the resulting ions we are able to monitor the system continuously during dissociation or rearrangement. We find that the predissociative lifetime for the 3R‴ (v′2 = 1) Rydberg state is about 150 fs. We demonstrate a powerful new technique using time-correlated femtosecond harmonic generation and laser light pulses to study the time evolution of ultrafast dynamic processes in molecules.
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| 2. |
- Bassler, M, et al.
(författare)
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Beam line 1411 at MAX II - performance and first results
- 2001
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Ingår i: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT. - : ELSEVIER SCIENCE BV. - 0168-9002. ; 469:3, s. 382-393
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Tidskriftsartikel (refereegranskat)abstract
- We report on the characteristics and first results from the soft X-ray beam line I411, based on an undulator at the third generation synchrotron facility MAX II, Sweden. The beam line is designed for high-resolution, angle-resolved electron spectroscopy o
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| 3. |
- Bässler, M., et al.
(författare)
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Beam line I411 at MAX II - Performance and first results
- 2001
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Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0168-9002. ; 469:3, s. 382-393
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Tidskriftsartikel (refereegranskat)abstract
- We report on the characteristics and first results from the soft X-ray beam line I411, based on an undulator at the third generation synchrotron facility MAX II, Sweden. The beam line is designed for high-resolution, angle-resolved electron spectroscopy on gases, liquids and solids. Main components are the modified SX700 monochromator and the end station, both of which were previously used at beam line 51 at MAX I. The end station is equipped with a rotatable SES-200 hemispherical electron-analyser. Before the end station, a one-metre section is reserved for exchangeable experimental set-ups. The usable photon energy range is 50-1500 eV and the photon flux is two orders of magnitudes higher compared to beam line 51. At 400 eV a resolving power of about 5700 in the first order of the monochromator grating could be obtained. In gas phase, a total electron energy resolution of 16 meV has been achieved. Detailed results on the undulator performance, flux, photon and electron energy resolution as well as some technical details are presented here. As an example of the capabilities of the beam line I411, we present the fully vibrationally resolved Auger resonant Raman electron spectrum of gas-phase N 2.
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| 4. |
- Marinho, R. R.T., et al.
(författare)
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Interference between direct and resonant channels in near-resonance photoemission in argon
- 2001
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Ingår i: Physical Review A. Atomic, Molecular, and Optical Physics. - 1050-2947. ; 63:3, s. 325141-325145
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Tidskriftsartikel (refereegranskat)abstract
- The photoelectron spectra of argon was demonstrated during resonant photoemissions. The interference effects of the photoelectron spectra of argon was monitored by following the intensity of final states through resonant and direct channels. The need for a unified one-description of the ionization through a direct and core-excitation mediated channel was described.
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| 5. |
- Sorensen, SL, et al.
(författare)
-
Femtosecond pump-probe photoelectron spectroscopy of predissociative Rydberg states in acetylene
- 2000
-
Ingår i: JOURNAL OF CHEMICAL PHYSICS. - : AMER INST PHYSICS. - 0021-9606. ; 112:18, s. 8038-8042 Language: English
-
Tidskriftsartikel (refereegranskat)abstract
- We employ a pump-probe approach to molecular photoionization to study fast dissociation of Rydberg states in acetylene. By using time-resolved photoelectron spectroscopy to study the electronic state of the resulting ions we are able to monitor the system
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| 6. |
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| 7. |
- Koertge, J., et al.
(författare)
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Vital exhaustion and recurrence of CHD in women with acute myocardial infarction
- 2002
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Ingår i: Psychology, Health & Medicine. - : Informa UK Limited. - 1354-8506 .- 1465-3966. ; 7:2, s. 117-126
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to investigate the prospective impact of vital exhaustion on recurrence after acute myocardial infarction (AMI) in women. Women ≤ 65 years, mean age = 55.30, SD = 7. 63, N = 110, consecutively admitted to a coronary care unit with AMI were examined after three-six months, and followed for five years. Vital exhaustion was assessed using an early version of the Maastricht Questionnaire. A recurrent event was defined as cardiac death, AMI or a revascularization procedure. Forty-five recurrent events were found (in 41% of the study group). One standard deviation (8.4 points) increase of vital exhaustion scores was associated with a 53 % increased risk of a new event and a score above the median was associated with a hazard ratio of 2.24 (95% CI 1.21-4.14). These results remained after adjusting severity of chest pain and significant coronary stenosis. In conclusion, it was found that vital exhaustion is a marker of poor prognosis in women with AMI. The relationship appears to be independent of signs of underlying disease, including severity of chest pain and significant coronary stenosis.
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| 8. |
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| 9. |
- Aoki, S., et al.
(författare)
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Identification of elastic/visco-plastic material constants under impact loading
- 2000
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Ingår i: IUTAM Symposium on Field Analysis for Determination of Material Parameters - Experimental and Numerical Aspects. - Dordrecht : Encyclopedia of Global Archaeology/Springer Verlag. - 1402012837
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Konferensbidrag (refereegranskat)abstract
- A method for identifying the material constants of an elastic/visco-plastic meterial under tensile impact loading is proposed. In this method, the Kalman filter and the finite element method are used together with a few test data. To obtain data for high strain rates, notched specimens are employed, because arbitrarily shaped specimens are available in this method. To increase the accuracy of identification, a test under a relatively low strain rate is needed in addition to a test under a high strain rate. The optimum strain rate is determined in such a way that the largest eigen value of the covariance matrix of the estimated parameters becomes minimum. A numerical simulation in performed to demonstrate the validity and usefulness of this method
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| 10. |
- Brandänge, S, et al.
(författare)
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Highly diastereoselective hydrogenations leading to ß-hydroxy ∂-lactones in hydroxy-protected form. A modified view of ∂-lactone conformations.
- 2003
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Ingår i: Journal of the American Chemical Society. - : American Chemical Society (ACS). - 1520-5126 .- 0002-7863. ; 125:39, s. 11942-11955
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Forskningsöversikt (refereegranskat)abstract
- Enol MEM ethers 4 and 15 and the corresponding enol acetates were hydrogenated over Pd/C with very high (>99%) diastereoselectivity to saturated -lactones. A stereochemical generalization can be formulated thus: trans-5,6-disubstituted 1-oxa-3-cyclohexen-2-ones (e.g. 14 and 15) are hydrogenated over Pd with high selectivity from the side trans to the C(6)-substituent. A mechanistic rationalization of the stereochemical outcome in the Pd-catalyzed hydrogenation of this as well as other types of substituted ,-unsaturated -lactones is presented. An analysis of X-ray crystallographic data for 67 compounds demonstrated a great conformational diversity of the saturated -lactone ring. Besides, ab initio calculations (HF/6-31G*) indicated a very high conformational mobility. Thus, the lowest calculated transition state for the conversion of the half-chair, most stable, conformer of -valerolactone to the boat-type conformer lies only 1.93 kcal/mol above the former. Beside these two conformers, also chair, envelope and skew conformations are accessible; all lie less than 2 kcal/mol above the half-chair. The previous conformational paradigm comprising only boat and half-chair types is incomplete
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